A NEW GENUS OF ANT-MIMICKING SPIDER WASPS 
FROM AUSTRALIA 
(HYMENOPTERA, POMPILIDAE)'* 
By Howard E. Evans 
Museum of Comparative Zoology 
Australia has a rich fauna of spider wasps ( Pompilidae) , but aside 
from numerous species descriptions by R. E. Turner, Frederick 
Smith, and others, it is almost totally unstudied. There would be 
little excuse for further species descriptions if it were not for two 
factors : ( i ) one of these species was figured in the recent book 
The Insects of Australia , where it was identified as simply “brachyp- 
terous Pepsini,” although it is such an unusual wasp that one is 
immediately curious as to its proper position in the classification ; 
and (2) these are among the most striking ant mimics known, and 
furthermore each of the two known species appears to mimic one 
particular species of ant. 
Ant mimicry is not wholly unknown in the Pompilidae. I regard 
some of the pale-bodied, banded-winged North American Ageniella 
as generalized ant mimics (e.g. A. conflicta Banks). Here the wing 
pattern creates the appearance of a wingless insect with several body 
constrictions, such as an ant. It is probable that some of the apterous 
and brachypterous 'Ctenoceratini of Africa are ant mimics, although 
Arnold (1932) suggests that some may mimic mutillids. 
In the present instance there seems little question that ant mimicry 
is involved, and it is possible to name the model in each case. The 
one figured in The Insects of Australia , here described as Iridomimus 
spilotus, is mounted on a card point on the same pin as a worker 
Iridomyrmex rubriceps Forel. 1 Although I know nothing of the cir- 
cumstances under which this was collected, the striking resemblance 
of the pompilid and the ant suggests that whoever collected them 
took them in close proximity and was impressed by this resemblance. 
* Published with the aid of a grant from the Museum of Comparative 
Zoology at Harvard College. 
J Ant determinations are by Dr. R. W. Taylor, Division of Entomology, 
C. S. I. R. O., Canberra, Australia. Dr. Taylor found that this specimen 
compared favorably with a syntype of what has been called Iridomyrmex 
gracilis var. rubriceps Forel, but he thinks it probable that rubriceps should 
be regarded as a full species, perhaps not closely related to gracilis. 
Manuscript received by the editor November 13, 1970. 
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